can conception date be wrong by ultrasound ?

i think i’m off by 3 weeks . my lmp was october 7 and ovulation day was the 21 and i was active during my fertile days , and i got what i thought was my period on october 30 and just thought it came early but only lasted two days and wasn’t much of a period and now i’m starting to over think that it could been implantation bleeding cause when i thought i was first pregnant in november i didn’t really get any type of bleeding at all just cramping. supposedly i’m 18weeks rn but now thinking about it calculating from october 21 that could been my ovulation day i would be 21 weeks rn instead 18 , but i’m very confused

Hi, have you posted before under a variation of this name? Your user name kind of rings a bell. If so, I'll look up the details.

When you determined that your ovulation day was October 21, was this because a doctor told you that you did? If not, what kind of calculation did you use? Have you been charting your cycles for a long time such that you can be certain your ovulation comes like clockwork?

supposedly my lmp was october 31 but i remembered i had my period before that on october 7th lasted 3 days as the usual and i had a light bleeding october 30-31 and i never get my period twice a month that was odd to me . i did some searching and calculating and my ovulation day after my period on october 7th it stated my ovulation day was the 21st of october and i DTD during my fertile days before ovulation and when i using the ovulation calculator and implantation calculator it stated that my implantation bleeding could have started the 30-31 could t be i mistaken that as my period and got the wrong conception date.

OK, let's see. You have said that your "ovulation date was" such and such or "supposedly" you are x weeks. Does any of this naming of dates come from a doctor? Especially, does any of this come from a doctor who gave you an ultrasound and then told you a due date because of what was seen on the ultrasound? Or is it all just by you doing calculations and looking at apps?

my doctor just went by my lmp that i told her i thought it was october 30 cause the two day bleeding but then i also told them i had a normal period the 7th of october for 3 days and i never get a period twice a month especially if it last 2 days .

bleeding october 7th(3 days normal period)
sex on the 15th of october with bf
sex on the 18th and 19th of october with bf
sex again on the 22nd with bf
according to the website i used to calculate ovulation date chances concieving was 17-21 , making 21 my ovulation day ,
bleeding on the 30th thinking it was my period but lasted 2 days which is odd especially the month i already had my period .
November no period, took a test dec. 3 was positive
saw a doctor december 13 and said i was 6 weeks and 2 days because she used october 30th as my lmp when i actually think it was my implantation bleeding . because november i didn’t have any implantation bleeding whatso ever .

(Incidentally, implantation bleeding is largely an Internet myth. An embryo is smaller than the dot on the i in this sentence, it would not bleed for two days when burrowing into the uterine lining. For all the women who write in hopefully saying they have had "implantation bleeding," only about one in 1,000 has ever reported that they figured out that is what they really had.) It's certainly possible to have a squirrelly period, and not unusual to have one right before getting pregnant either. But nothing about your story sounds like you conceived as early as having implantation on the 30th of October would have you conceive. The baby would have appeared on the ultrasound as an eighth-week baby, for one thing. A doctor can tell the difference between a sixth-week baby and an eighth-week baby at a glance.

Actually, now that I look at it, the baby (if it implanted on October 30) would be in its ninth week when she told you it was 6w2d along. You're asking if somehow the "conception measured by ultrasound" was wrong. This is asking if a qualified medical doctor and an ultrasound tech will confuse an embryo of a certain size and developmental markers for one several weeks' different amount of development. No. They will not confuse two embryos of such different ages.

Is the problem that you slept with your boyfriend in October and then slept with someone else in November? Or is your boyfriend the only guy? (If so, why are you so worried about when conception was?)

Here's the deal. When a doctor looks at and measures the actual embryo by ultrasound, if it is in a certain time period (neither too early to see nor too late in the pregnancy to be reliable), it would not matter if you told her your last period was three years ago. She would not use that date if it conflicted with the evidence she saw when measuring the baby with the ultrasound. A doctor will even determine a calculated first day of your last period if necessary, working from the age of the embryo.

If your doc did an ultrasound that early in the pregnancy and gave you a due date, rely on that due date.

The Content on this Site is presented in a summary fashion, and is intended to be used for educational and entertainment purposes only. It is not intended to be and should not be interpreted as medical advice or a diagnosis of any health or fitness problem, condition or disease; or a recommendation for a specific test, doctor, care provider, procedure, treatment plan, product, or course of action. MedHelp is not a medical or healthcare provider and your use of this Site does not create a doctor / patient relationship. We disclaim all responsibility for the professional qualifications and licensing of, and services provided by, any physician or other health providers posting on or otherwise referred to on this Site and/or any Third Party Site. Never disregard the medical advice of your physician or health professional, or delay in seeking such advice, because of something you read on this Site. We offer this Site AS IS and without any warranties. By using this Site you agree to the following Terms and Conditions. If you think you may have a medical emergency, call your physician or 911 immediately.